Various means have been used in the prior art to thread an externally threaded base member into an internally threaded projectile housing. In order to accomplish the torquing necessary to join both members frequently assembly slots had to be machined into the work piece. Machining operations to the base member work piece in the form of slots, holes or grooves to facilitate transmission of torque was frequently time consuming and costly to produce. The prior art frequently required manual assembly of the threaded part members in order to prevent the work piece from slipping out of the attachment slots and causing damage to the work piece.